Massive storms over the Alps
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forecast valid from 06.00 to 23.59 UTC on Friday 26 July
The hegemony of the North African high pressure ends under the blows of an imposing Atlantic perturbation that will literally break through, with its load of cold air, from the western quadrants, determining a perturbed weekend on most of Italy.
At the end of this summer break we will certainly count the damage for very violent phenomena.
Tomorrow will see a first baric collapse with thunderstorms mostly for relief purposes.
The jet stream (current of air present in free atmosphere that "transports" thunderstorms) will tend to dispose from west / south west with sharp and sudden destabilization of the air column
The abnormal energy in play will facilitate the formation of violent thunderstorms with the possibility of medium-large hailstorms.
Veneto, Friuli Venezia Giulia e Emilia Romagna
Thunderstorms that will develop during the early afternoon on the alpine reliefs. South-eastern ventilation on the lower Veneto will drag energy values (Cape) between 2500 and 2800 J / kg up to the Alps, with a serious risk of high intensity phenomena (Level 2-3 Alpine area). Indeed, storms, floods, landslides and medium-large hailstones are likely to occur. We strongly advise against outings especially on the exposed ridges.
The storms will move from west to east, affecting the entire Alpine and pre-Alpine area of Friuli by late evening.
Trespassing on the high plains is not excluded.Between late afternoon and evening, some parameters pushed to the limit suggest a sudden trigger in the middle of the plain on the border between Emilia and Veneto.
On these areas a convergence will take place between the humid south-east rising from the Adriatic and the drier sw from the Apennines, towards evening the outflow of the alpine storms could even create a triple point of convergence.
The trigger at high altitude to trigger this bomb ready to jump appears really bland but if it were to trigger, the storm would find an abnormal energy to be exploited with peaks above 3000J / kg and the possibility of large hailstones (> 5 cm), flooding and Tornado
P.Š. Only level 2 was issued due to doubts about the trigger, possible raising to 3 in case of further confirmation by the models.
Alps (Level 1) And appennines
Afternoon phenomena with hail and in some cases local flooding, local and temporary trespassing on the neighboring plains are not excluded.
Jacopo Zannoni
The member of the storm chasers group ZenaStormChaser from Genoa, Italy. Follow ZenaStormChaser on Facebook, Instagram or Twitter
